Make it clearer that catalog_search_range is an epicentral distance

Author: claudiodsf

requake/config/configspec.conf

@@ -59,7 +59,8 @@ catalog_depth_max = float(default=60)
 ## magnitude selection
 catalog_mag_min = float(default=2)
 catalog_mag_max = float(default=4)
-## maximum distance range to search for similar earthquakes (radius, km)
+## maximum epicentral distance range to search for similar earthquakes
+## (radius, km)
 catalog_search_range = float(default=30)
 ## trace id(s) to compute cross-correlation, in NET.STA.LOC.CHAN format.
 ## Waveform data for this trace(s) id will be retrieved using the station